Known label printing apparatuses are disclosed in EP-A-322918 and EP-A-322919 (Brother Kogyo Kabushiki Kaisha) and EP-A-267890 (Varitronic). The label printing apparatuses each include a cassette receiving bay for receiving a cassette or tape holding case. In EP-A-267890, the tape holding case houses an ink ribbon and a substrate tape, the latter comprising an upper image receiving layer secured to a backing layer by an adhesive. In EP-A-322918 and EP-A-322919, the tape holding case houses an ink ribbon, a transparent image receiving tape and a double sided adhesive tape which is secured at one of its adhesive coated sides to the image tape after printing and which has a backing layer peelable from its other adhesive coated side. With both these apparatus, the image transfer medium (ink ribbon) and the image receiving tape (substrate) are in the same cassette.
It has also been proposed by the present applicants in, for example, EP-A-578372 to house the ink ribbon and the substrate tape in separate cassettes.
In all of these cases, the image receiving tape passes in overlap with the ink ribbon to a print zone consisting of a fixed print head and a platen against which the print head can be pressed to cause an image to transfer from the ink ribbon to the image receiving tape. There are many ways of doing this, including dry lettering or dry film impression, but the most usual way currently is by thermal printing where the print head is heated and the heat causes ink from the ink ribbon to be transferred to the image receiving tape.
In other known tape printing apparatuses, so-called direct thermal tapes are used, in which an image is created directly onto the direct thermal tape without the interposition of an ink ribbon cassette. Elements of a print head are heated, and the heat causes chemicals within the direct thermal tape to react and produce an image in or on the tape.
The apparatuses of the type described above are provided with a keyboard which enables a user to enter characters, symbols and the like to form an image to be printed by the tape printer. The keyboard usually has text character keys and number keys for entering letters and numbers respectively, plus some function keys which, among other things, operate menus and allow printing attributes to be set.
“Stand-alone” label printers can be distinguished from “label printer systems”, which comprise a printer connected to a PC or other computing device. In such label printer systems, a user creates or edits a label for printing using a PC, and then sends print data to a printer to cause the printer to print the print data onto a label medium. In such label printer systems, the user will view a display of the PC to create a label, rather than a display of the printer. Also, the label-editing software used for creating the label will be stored and run on the PC, rather than the printer.
In contrast, stand-alone label printers are operable independently of a PC or other computer to create and print a label. Although some stand-alone printers are connectable to a PC or other computer to receive some data, they are nevertheless operable independently of the PC or other computer to create a label for printing, since label-editing software used for creating the label is stored and run on the label printer itself. Stand-alone label printers thus usually include an integral display via which the user can view an interface of the label-editing software.